1. Field of the Invention
One aspect of the invention relates to a wireless device, in particular, to a wireless device including a touch panel configured by a display device and a touch sensor.
2. Description of the Related Art
A touch panel configured by combining a touch sensor and a display device such as a liquid crystal panel is used as an operation input means for various electronic devices, for example, mobile phones, handheld terminals, copiers, portable game machines, electronic dictionaries, car navigators, electric appliances, automatic ticket vending machines, cash dispensers, etc.).
In such a touch panel, since the operation keys displayed on a screen of the display device can be set up variously and freely by the software, greater flexibility of operation input is obtained compared to a mechanical operation key.
However, any attempts to use the touch panel in small wireless devices such as mobile phones will face various challenges. In order to have multiple and diverse functions like recent mobile phones and as well as obtaining an easily visible display, it is necessary to form the screen size of the display device as large as possible. Furthermore, a circuit substrate or a battery may be housed in a space formed in the rear of the display screen. Thus, in order to arrange an antenna, which is an essential part of the wireless device, within a casing, it is necessary to utilize the limited space formed on the periphery of the casing and outside the frame of the display screen.
The peripheral portion of the casing corresponds to the periphery of the touch sensor mounted so as to cover the display screen, and in addition an electric line for signaling information regarding a detected position is mounted in the vicinity of the periphery of the casing. Thus, if such line approaches the antenna, there is concern it will have an unfavorable influence on a characteristic of the antenna (for example, a decrease of impedance, electromagnetic interference, etc.).
As a technique to address such an issue, a technique where the antenna is built in the display device including a touch panel is known (See JP-A-2006-48166, 5 and 8 pages, FIGS. 2 and 8). The touch panel of the display device disclosed in JP-A-2006-48166 has an operation unit which is a region where touch operation is able to be performed, and a frame unit formed therearound, and further includes an antenna unit in a part of the frame unit.
For the display device disclosed in JP-A-2006-48166, as shown in FIG. 8 of JP-A-2006-48166, the antenna is mounted in the frame unit of the touch panel, specifically, a position overlapped with a support substrate of the touch panel when viewed from a direction perpendicular to the display screen. Thus, disposing the entire antenna in a position overlapped with the substrate may cause unfavorable issues in the light of the characteristic of the antenna described above.